crypto: omap - Use GCM IV size constant

This patch replace GCM IV size value by their constant name.

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/omap-aes-gcm.c b/drivers/crypto/omap-aes-gcm.c
index 7d4f8a4..9b8f1c7 100644
--- a/drivers/crypto/omap-aes-gcm.c
+++ b/drivers/crypto/omap-aes-gcm.c
@@ -18,6 +18,7 @@
 #include <linux/omap-dma.h>
 #include <linux/interrupt.h>
 #include <crypto/aes.h>
+#include <crypto/gcm.h>
 #include <crypto/scatterwalk.h>
 #include <crypto/skcipher.h>
 #include <crypto/internal/aead.h>
@@ -311,7 +312,7 @@ static int omap_aes_gcm_crypt(struct aead_request *req, unsigned long mode)
 	int err, assoclen;
 
 	memset(rctx->auth_tag, 0, sizeof(rctx->auth_tag));
-	memcpy(rctx->iv + 12, &counter, 4);
+	memcpy(rctx->iv + GCM_AES_IV_SIZE, &counter, 4);
 
 	err = do_encrypt_iv(req, (u32 *)rctx->auth_tag, (u32 *)rctx->iv);
 	if (err)
@@ -339,7 +340,7 @@ int omap_aes_gcm_encrypt(struct aead_request *req)
 {
 	struct omap_aes_reqctx *rctx = aead_request_ctx(req);
 
-	memcpy(rctx->iv, req->iv, 12);
+	memcpy(rctx->iv, req->iv, GCM_AES_IV_SIZE);
 	return omap_aes_gcm_crypt(req, FLAGS_ENCRYPT | FLAGS_GCM);
 }
 
@@ -347,7 +348,7 @@ int omap_aes_gcm_decrypt(struct aead_request *req)
 {
 	struct omap_aes_reqctx *rctx = aead_request_ctx(req);
 
-	memcpy(rctx->iv, req->iv, 12);
+	memcpy(rctx->iv, req->iv, GCM_AES_IV_SIZE);
 	return omap_aes_gcm_crypt(req, FLAGS_GCM);
 }